褪黑素对乳鼠缰核神经元延迟整流钾电流的作用

发布时间：2018-06-02 02:53

本文选题：缰核 + 昼夜节律　；参考：《吉林大学》2006年硕士论文

【摘要】： 缰核是边缘前脑至中脑的重要枢纽,它与睡眠-觉醒周期相关的上下位结构均有着密切的神经解剖学联系,是参与调节昼夜节律的重要核团之一。褪黑素(MT)由松果腺在光照的导引下和在下丘脑视交叉上核(SCN)的控制下,节律性地合成和分泌的吲哚胺类激素。白天MT的分泌受到抑制,黑夜MT大量合成和分泌。这种节律性的分泌方式对于生物节律的形成是重要的。本文采用在急性分离的大乳鼠缰核神经元细胞膜片钳记录方法,在昼夜周期的不同时相(白天的CT10-12;CT12-14;CT14-16和夜晚的CT20-22; CT22-24; CT0-2)记录缰核延迟整流钾离子电流,观察大乳鼠缰核神经元延迟整流钾电流的昼夜节律性以及褪黑素的作用。实验结果显示:(1)缰核神经元延迟整流钾电流具有自主的昼夜节律,电流幅度黑夜高,白天低。(2)无论在白天还是黑夜,褪黑素能明显增加缰核神经元延迟整流钾电流。(3)褪黑素增加的缰核延迟整流钾电流的程度在黑夜高,在白天低。这说明缰核神经元上的钾离子通道开放的自主昼夜节律性可能是缰核神经元昼夜节律性形成的离子基础;褪黑素调节缰核的昼夜节律性可能是通过对钾离子电流起作用的,而缰核对褪黑素的敏感性显示有昼夜的不同进一步提示钾离子电流在缰核昼夜节律形成中的作用,其机制有待更深入的研究。
[Abstract]:Habenular nucleus is an important hub from the marginal forebrain to the midbrain. It has a close neuroanatomical relationship with the upper and lower structures associated with the sleep-wake cycle and is one of the important nuclei involved in the regulation of circadian rhythm. Melatonin (MTT) is rhythmically synthesized and secreted by the pineal gland under the guidance of light and under the control of the supraoptic nucleus of the hypothalamus (SCN). The secretion of MT was inhibited during the day and a large number of MT was synthesized and secreted in the night. This rhythmic way of secretion is important for the formation of biological rhythms. A patch-clamp recording method was used to record delayed rectifier potassium ion currents in habenular nucleus of neonatal rats at different periods of day and night (day CT10-12 CT12-1414 CT14-16 and night CT20-22; CT22-24; CT0-2). To observe the circadian rhythm of delayed rectifier potassium current in habenular nucleus neurons and the effect of melatonin. The results show that the delayed rectifier potassium current of habenula neurons has its own circadian rhythm, the amplitude of current is high in night and night, and the amplitude of current in day is low. Melatonin significantly increased delayed rectifier potassium current in habenular nucleus neurons. This suggests that the spontaneous circadian rhythm of potassium channel opening in habenular nucleus neurons may be the ionic basis of circadian rhythm of habenular nucleus neurons, and melatonin may regulate the circadian rhythm of habenular nucleus by acting on potassium ion currents. The sensitivity of habenular nucleus to melatonin showed diurnal variation further suggesting the role of potassium ion current in the formation of circadian rhythm in habenular nucleus and its mechanism needs further study.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2006
【分类号】：R33

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